The invention is to be applied to an integrated circuit (IC) operational amplifier (op-amp) which is intended for operation at low power and a high slew rate (speed). Typically, such devices are programmable by the user who can, by selecting suitable external components, set the electrical characteristics of the circuit. By operating the op-amp at a higher current the user can increase its speed and transconductance. However, when lower values are acceptable, a lower operating current can be tolerated, the power consumption and dissipation can be lowered. This gives the user a greater design latitude in the form of programmability.